David Cameron is a pilot who can't get his undercarriage up. His leadership of the Tory party left the runway with impressive speed, considerable élan and a strong following wind from a friendly media. But now he is struggling to gain any altitude. I sniff the sweet smell of panic in the Tory leader's cockpit about what he and his modernisers can do before the right wingers in their party try to storm the pilot's cabin.

You can see why they are getting a little frantic. David Cameron had a dream start, the most sun-blessed honeymoon a new Tory leader could ask for. To him was gifted a divided Labour party, an embarrassed Liberal Democrat party, a Conservative party willing him to be a success and a benign press drooling over his every photo-opportunity; his wife even provided a new baby to kiss.

He has also been given a lot of space to fashion his own image. He has been allowed to define himself positively rather than be branded negatively by his opponents because Tony Blair and Gordon Brown couldn't agree how to attack him and the Lib Dems were too busy humiliating themselves.

The Prime Minister and the Chancellor are feuding so poisonously that attempts to stage shows of unity between the two only highlight how divided they are. It is a commentary on the state of the relationship that it is regarded as remarkable that they managed to share a car journey to the launch of their party's local elections campaign last week.

More revealing about that tortured relationship is what actually happened when the two men were forced into each other's company on the back seat of the limo. The Prime Minister tried to engage the Chancellor in conversation. I'm told that Mr Brown responded by taking out some papers and burying himself behind them, refusing to reply to every overture until Mr Blair finally gave up trying to make conversation. The journey passed in a bitter silence.

The Prime Minister could only get his education legislation past his backbench rebels by relying on the support of the official opposition. Hospitals are sacking staff after record increases in spending on the health service which should play perfectly to the Tory claim that Labour mismanages public services and squanders taxpayers' money. Scotland Yard is investigating allegations that the Prime Minister was involved in the selling of peerages.

And yet the electorate, disenchanted as much of the public might be with the government, is not responding to all this by swooning gratefully into the arms of the Tory young pretender. Do not believe David Cameron and his allies when they are dismissive of disappointing opinion polls. If polls were of so little account to them, the Tories would not spend so much money on their own private polling. That, I've learnt, is giving them the same message as the published surveys. The honeymoon is over.

One man who clearly takes the polls seriously is the Tory party chairman. The role has traditionally been to whip up the troops. Francis Maude prefers to sober them up. He even mocks himself for being a 'gloomfest'. Some of his colleagues have reacted angrily his suggestion that the Conservatives could lose the next election. I don't think he is being defeatist. He is being a realist. It requires only a small swing to deprive Labour of its majority at the next election, but it demands a pretty mammoth shift for the Conservatives to win a majority of their own.

There are several explanations for why David Cameron cannot get more uplift. What damages the government does not necessarily rebound to the advantage of the Conservatives. The Tories haven't come out of the latest eruption of ugly headlines about party funding looking any cleaner than Labour. Whatever the government has got wrong about the NHS, the public is a long way from being convinced the Conservatives would get it right.

For all Labour's troubles, there is a brute strength to this government backed by years of sustained prosperity. One member of the cabinet who represents a seat in the Midlands recalls canvassing an estate of council houses in his constituency at the last election and being staggered by the quality of the cars he saw outside many homes. He was particularly astounded to see a Ferrari parked in one drive. You can make people extremely irritated with a long-standing government, but it is hard to get them absolutely furious during a period when most people have become better off.

The electorate's negative feelings towards the Conservative party are too deeply embedded to be simply magicked away by David Cameron sporting his Converse trainers and saying he will stick a wind turbine on the roof of his new house. A revealing poll by ICM for Channel 4 News had well over half of the respondents agreeing with the proposition that Mr Cameron was a new face, but his party hadn't really changed at all.

This presents him with a big problem and a form of consolation. At least it provides him with a temporary alibi which he and his allies have eagerly seized on to try to head off attacks on his approach from the rumbling right. Nice leader, shame about our party. That has been the thrust of the message, albeit delivered in code, to the Tory spring conference in Manchester this weekend. The chairman told them that there was nothing wrong with David Cameron in the eyes of the electorate. 'People really do think he is the goods,' said Mr Maude, using the ad-speak for which the Tory modernisers have a profound weakness. 'We now need to convince them that the whole party has changed.'

Mr Cameron was right to move quickly to change his party, but the very rapidity of what he has done is bound to breed questions in the mind of the sceptical public about the sincerity and depth of his modernisation of the Conservatives.

When Tony Blair took over the Labour party, it had been set on a modernising trajectory for some years. He could locate his leadership in a narrative of change that had begun 11 years earlier with Neil Kinnock. What Labour took more than a decade to manage, David Cameron is trying to achieve in a much shorter time. The voters are understandably suspicious when a party tries to present itself as an overnight convert.

To the regret of some of his allies, David Cameron has yet to find his 'Clause Four moment'. He has not found a symbolic act of change as potent as Tony Blair's rewriting of the Labour constitution. The Tories are not getting a great burst of energy and drama out of putting a statement of values to a vote of the party membership. If Mr Cameron gets, as I suspect he will, a crushing Saddamite majority in favour of his document, then it will be written off as a meaningless exercise.

In his opening period as leader, he secured a lot of attention and momentum from his apparently breathless frenzy to change his party. Barely a week passed without him dumping a traditional Tory policy or launching a new commission. After all that frenetic activity, the novelty is bound to wear off. George Osborne, the shadow chancellor, told the conference that it was not enough for them to 'critique' the government. They also had to demonstrate their 'alternative'. Quite right. And yet his Labour-bashing speech was very light on detailed policy.

I see the sense of not making policy in haste. The Conservatives don't want to burden themselves with too many detailed commitments too early in a long game. By the time of the next election, which might be more than four years away, policies announced now could look dated or stupid. Any ideas that seem attractive will probably be nicked by New Labour.

The downside to having little policy is that it compounds the disadvantages of the youth and inexperience of Mr Cameron and Mr Osborne. The negative suggestion about the Cameron Conservatives that resonates most with private focus groups is that they are all sales pitch and no product.

That is beginning to prick them. David Cameron is suddenly saying that he will not wait 18 months for his environment commission to report before he comes up with some proposals for curbing greenhouse gases. He will shortly produce his own version of the climate-change levy on polluters. That whiffs of panic which, in turn, suggests that the disappointing news from the polls is beginning to eat into their discipline.

William Hague, IDS and Michael Howard all began their leaderships of the Tory party saying they would pitch to the centre ground. When they failed to make progress and came under internal pressure, all three lurched off to the right.

David Cameron understands that he has to break with the pattern which has consigned his party to three consecutive election defeats. In his speech yesterday morning, he told his party that they cannot go back. His sensible colleagues know that their leader is correct. That will not calm their increasingly unquiet desperation if he cannot show how they will move forward. There is some serious turbulence ahead for this sky jockey.